Doctor roll



A. F. SHIELDS Jan. 16, 1962 DOCTORROLL Filed July 28, 1958 fri;

ff @L atent lildld Patented dan. 16, 1952 duce 3,016,874 DUCTOR RQLLAlbert i?. Shields, Forest Hiils, N.Y., assigner to S d; S CorrugatedPaper Machinery Co., liuc., Brooklyn, N.Y., a corporation of New YorkFiled July 2S, 1958, Ser. No. 751,252 6 Claims. (Cl. 11S- 262) Theinstant invention relates to a novel construction for a doctor rollwhich is used in conjunction with a glue appiying roll in automatic boxforming machinery.

ln automatic box forming machinery, the glue applying roll is rotated athigh speed while being partially submerged in a solution of glue. inorder to insure that a. uniform and controlled layer of glue will betransferred to the box ap or tape, a doctor roll is placed adjacent tothe glue applying roll. It has been the practice to rotate the doctorroll as well as the glue applying roll. r[his has often resulted inforcing the excess glue to be thrown by the doctor roll against thesides of the glue applying roll. The glue on the sides of the high speedglue applying roll is often thrown so that it strikes areas of the boxblanks which should be free of glue thereby providing defective boxes.

ln this invention, l propose to have a doctor roll which is freelymounted rather than being driven. The doctor roll is provided with adepression into which the outer portion of the glue applying roll isentered. There is a friction film of glue between the sides of the glueapplying roll and the walls which form the doctor depressions therebycausing rotation of the doctor roll with the film viscous glue i'luidacting as a driving connection. This avoids throwing of the excess glueto the sides of the glue applying roll and also enables the doctor rollto clean itself.

The free ends of the walls which form the depression are curvedoutwardly from the depression and away from the doctor roll rotationalaxis so that surface tension causes the excess glue to be pulled awayfrom the sides of the glue applying roll. The outer edges of theoutwardly curved surfaces are sharp, thereby assuring that the excessglue will not run down the sides of the doctor roll but will insteaddrop from the outwardly curved surface directly into the glue Solution.

Accordingly, a primary object of the instant invention is to provide anovel doctor roll means for controlling the glue layer on a glueapplying roll of a high speed automatic machine.

Another object is to provide a doctor roll which is frictionally drivenby the glue applying roll through a lm of viscous glue iluid.

A still further object is to provide a doctor roll having a depressionand outwardly curved surfaces on the free ends of the walls which formthe depression, with the depression being positioned to receive theperipheral edge of the glue applying roll.

A further object is to provide a doctor roll in which the outer edges ofthe curved surfaces at the free ends of the walls forming a depressionin the roll, are maintained as sharp edges rather than being curved.

These as well as other objects of the instant invention shall becomereadily apparent after reading the following description of theaccompanying drawings in which:

FGURE l is a cross-section of my novel doctor roll means taken throughthe lines 1-1 of FIGURE 2 looking in the direction of the arrows 1 1.

FIGURE 2 is a side elevation illustrating the doctor roll means ofFIGURE l in working engagement with a glue applying roll.

FIGURE 3 is a cross-section taken through line 3 3 of FlGURE l lookingin the direction of arrows 3-3.

Referring to the figures, doctor roll is operatively positioned adjacentto glue applying roll 11 which is mounted on shaft 12 journalled in theside walls of glue pan 13. Glue applying roll 11 is driven at a highspeed synchronized with the machine in which it is incorporated. Such amachine may comprise an automatic box folding machine of the typedescribed in my copending application 509,329, filed May 18, i955.

Pan 13 is secured in a suitable manner to frame 14 of the machine.Doctor roll 10 comprises a cylindrical section 15 having spaced apartcircular walls 16 and 17 extending radially therefrom. The space betweenoutwardly curved walls 16 and 17 provide a depression into which theperipheral edge of glue roll 11 is entered. The free ends of each of thecircular walls 16, 17 are concavely curved outwardly from the depressionaway from the axis about which doctor roll 10 is free to rotate.

A stud 2t?, having a narrow shoulder section 21, extends throughopenings 22, 23 in the side walls of pan 13 and through opening 24 offrame 14 with shoulder 21 abutting frame 14. Nut 25 engages the free end26 of stud 20 to drive shoulder 21 snugly against frame 14 and securestud 20 in place. Sleeve Sii, having a central opening therethrough,surrounds the portion of stud 20 extending to the right (with respect toFIGURE l) from shoulder 21. A portion 31 of the outer surface of sleeve30 is eccentric with respect to the bore therethrough. The remainingportion 32 of the outer surface of sleeve 30 is concentric with respectto the bore therethrough.

An adjusting sleeve 33 is entered over the concentric portion of sleeve3u and is lixedly secured thereto by means of set screws 34, 35 whichengage the outer surface 32. Adjusting sleeve 33 as well as sleeve 3i)extend through opening 23. A washer 36, abutting flange 37' at the endof adjusting sleeve 33 is positioned externally of glue pan 13. Wing nut37 engages the threads at the end 38 of stud 2i). By rotating wing nut37 so that it moves toward pan 13, washer 36 forces adjusting sleeve 33and sleeve 3u secured thereto to the left with respect to FIGURE 1thereby forcing sleeve 3u into high pressure contact with washer 61,positioned on stud 20 within pan 13 adjacent to shoulder Z1, to locksleeve 30 endwise as well as prevent rotation thereof.

Adjusting sleeve 33 is secured to sleeve 3d in such a position that thespace between the end 39 of adjusting sleeve 33 and washer 61 isslightly greaterI than the length of cylindrical section 15. Doctor roll1@ is mounted for free rotation on the outer concentric surface 31 ofsleeve 30.

It is to be noted that doctor roll 1@ is freely mounted on sleeve 30.Rotational motion is imparted to doctor roll 10 by glue roll 11 througha ilm of glue which nds its way between the outer walls 40, 41 of glueroll 11 and the inner surface 42, 43 respectively of cavity formingwalls 16, 17. It is also to be noted that sharp edges 44, 45 areprovided at the free ends of the outer surface of walls 16, 17respectively.

The angular position of sleeve 3i) determines the spacing between doctorroll 10 and glue applying roll 11 which in turn determines the thicknessof the coat of glue which will be applied by the glue applying roll 11.

Adjustments of sleeve 30 are accomplished by loosening Wing nut 37 andgrasping ange 37 to rotate sleeve 30 about stud Ztl. As flange 37' isrotated the distance between the eccentric surface 31 of the sleeve andgiue roll 11 will change thereby changing the distance between thedoctor roll 10 and glue roll 11.

The depression formed by walls 16, 17 and cylindrical section 15 issubstantially rectangular in cross-section. Peripheral edge Sil of glueroll 11 is closely spaced with respect to the bottom surface 51 of thedepression. Edge 5t) passes through glue solution 52 in pan 13 andexcess amounts of glue adhering thereto are removed therefrom by doctorroll 10.

The excess so removed is carried away from the outer walls 40, i1 of theglue roll because of the curved surfaces at the free ends of walls 16and 17. Since edges 44, 45 are sharp the excess glue will not move overthe edges 44, 4S but instead will fall into the glue bath 53. In thisway the excess glue is not splattered by either the gluing roll 1li orthe doctor roll 10.

Although 1 have here described preferred embodiment of my novelinvention, many variations and modications will now be apparent to thoseskilled in the art, and I therefore prefer to be limited, not by thespecific disclosure herein, but only by the appending claims.

i claim:

1. The combination of a rotatable gluing roll and a rotatable doctorroll in operative position with respect to said gluing roll to removeexcess glue which may adhere to said gluing roller said doctor rollhaving a depression in the peripheral edge thereof into which saidgluing roll is entered, said depression being partially defined by apair of walls, said walls being positioned substantially normal totheaxis about which said gluing roll is rotated, said doctor roll alsoincluding curved surfaces at the free ends of said'walls, meansfor'adjusting` the spacing between the axes of rotation of said gluingand said doctor rolls tothereby adjust the thickness of 'a glue filmapplied by said gluing roll.

2. The combination of a rotatable gluing roll and a rotatable doctorroll in operative position with respect to saidl gluing roll to removeexcess glue which may adhere to said gluing roller said doctor rollhaving a depression in the peripheral edge thereof into which saidgluing roll is entered, said depression being partially defined by apair of walls, said walls being positioned substantially normal to theaxis about which said gluing roll is rotated, said doctor roll alsoincluding curved surfaces at the free ends of said walls; said surfacesbeing outwardly curved from said depression and away from the axis ofrotation of said doctor roll, means for adjusting the spacing betweenVthe axes of rotation of said gluing and said doctor rolls to therebyadjust the thickness of a glue film applied by said gluing roll.

3. The combination of avrotatable gluing roll and a rotatable doctorroll in operative position with respect to said gluing roll to removeexcess glue which may adhere to said gluing roller said doctor rollhaving a depression in the peripheral edge thereof into which saidgluing roll is entered, said depression being partially defined by apairof walls, said walls being positioned substantially normal to theaxis about which said gluing roll is rotated, said doctor roll alsoincluding curved surfaces at the free ends of said Walls, said surfacesbeing outwardly curved from said depression and away from the axis ofrotation of said doctor roll, said surfaces having sharp edges oppositethe edges bounding said depres sion, means for adjusting the spacingbetween the axes of rotation of said gluing and said doctor rolls tothereby adjust the thickness of a glue film applied by said gluing roll.

4. The combination of a rotatably driven gluing roll partially enteredinto a glue solution and a doctor roll freely mounted for rotation andoperatively positioned to close proximity to said gluing roll to removeexcess amounts of glue which may adhere to said gluing roll, means foradjusting the spacing between the axes of rotation of said gluing andsaid doctor rolls to thereby adjust the thickness of a glue iilrnapplied byv said gluing roll, said means including an eccentric meansmounted to the doctor roll axis of rotation, said doctor roll having adepression formed in the peripheral surface thereof to receive saidgluing roll, said doctor roll being rotated by said gluing roll by meansof a glue film positioned between walls, bounding said depression, andthe side walls` of said gluing roll, said doctor roll also includingcurved surfaces at the free ends of said walls.

5. The combination of a rotatably driven gluing roll partially enteredinto a glue solution and a doctor roll freely mounted for rotation andoperatively positioned in close proximity to said gluing roll to removeexcess amounts of glue which may adhere to said gluing roll, means foradjusting the spacing between the axes of rotation of said gluing anddoctor rolls to thereby adjust the thickness of a glue film applied bysaid gluing roll, said doctor roll having a depression formed in theperipheral' surface thereof to receive said gluing roll, said doctorroll being rotated byv said gluing roll by means of a glue filmpositioned between walls, bounding said depression, and the side Wallsof said gluing roll, said doctor roll also including curved surfaces atthe free ends of said Walls, said surfaces being outwardly curved fromsaid depression and away from the axis of rotation of said doctor roll.

6. rThe combination of a rotatably driven gluing roll partially enteredinto a glue solution and a doctor roll freely mounted for rotation andoperatively positioned in close proximity to said gluing roll to removeexcess amounts ofV glue which may adhere to said gluing roll, means foradjusting the spacing between the axes of rotation of said gluing andsaid doctor rolls to thereby adjust the thickness of a glue film appliedby said gluing roll, said doctor roll having a depression formed in theperipheral surface thereof to receive said gluing roll, said doctorrollbeing rotated by said gluing roll by means of a glue film positionedbetween walls, bounding said depression, and the side walls of saidgluing roll, said doctor roll also including curved surfaces at the freeends of said walls, said surfaces being outwardly curved from saiddepression and away from the axis of rotation of said doctor roll, saidsurfaces having sharp edges opposite the edges bounding said depression.

References Cited in the tile of this patent UNITED STATES PATENTS305,895 Conwell Sept. 30, 1884 634,805 Craw Oct. 10, 1899 1,549,576 LaBombard et al. Aug. 11, 1925 1,928,160 Watkins et a1. Sept. 26, 19332,066,782 King Jan. 5, 1937 2,517,746 Whelton et al. Aug. 8, 19502,682,254 Nicholson June 29, 1954 2,753,838 Jalbert July 10, 19562,767,683 Foley Oct. 23, 1956 2.812.739 Fleischauer Nov. 12, 1957

